/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package mobileAPI;

import entity.Comments;
import entity.Enrollment;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import jpa.controllers.EnrollmentJpaController;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;

/**
 *
 * @author Geymen
 */
public class CourseCommentsListServlet extends HttpServlet {

    /**
     * Processes requests for both HTTP
     * <code>GET</code> and
     * <code>POST</code> methods.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        
        Integer courseID;
        courseID = Integer.valueOf(request.getParameter("courseID"));
        
        //********************************
        
        // First get all comments of the course
        EnrollmentJpaController enrollmentJpaController = new EnrollmentJpaController();
        List<Enrollment> enrollmentList = enrollmentJpaController.findEnrollmentEntitiesWithCourseID(courseID);
        List<Comments> commentsList = new ArrayList<Comments>();
        for (Iterator<Enrollment> it = enrollmentList.iterator(); it.hasNext();) {
            Enrollment tempEnrollment = it.next();
            if (tempEnrollment.getCommentsList() != null) {
                commentsList.addAll(tempEnrollment.getCommentsList());
            }
        }

        //********************************
        
        // Second generate a map list of comments
        ArrayList commentMapList = new ArrayList();
        for (Iterator<Comments> it = commentsList.iterator(); it.hasNext();) {
            Comments comment = it.next();
            
            Map commentMap = new HashMap();
            commentMap.put("commentID",         new Integer(comment.getId()));
            commentMap.put("commentDetail",     new String(comment.getComment()));
            commentMap.put("commentDate",       new String(comment.getSysdate().toString()));
            commentMap.put("commentUserName",   new String(comment.getEnrollmentId().getUserId().getName()));
            commentMapList.add(commentMap);
        }

        //********************************
        
        // Forth generate a JSONObject object containts JSONArray
        JSONArray commentsListJSONArray = JSONArray.fromObject(commentMapList);
        JSONObject respondJSONObject = new JSONObject();
        respondJSONObject.element("courseCommentsList", commentsListJSONArray);

        try {
            /* TODO output your page here. You may use following sample code. */
//            out.println("<!DOCTYPE html>");
//            out.println("<html>");
//            out.println("<head>");
//            out.println("<title>Servlet CourseCommentsListServlet</title>");            
//            out.println("</head>");
//            out.println("<body>");
//            out.println("<h1>Servlet CourseCommentsListServlet at " + request.getContextPath() + "</h1>");
//            out.println("</body>");
//            out.println("</html>");
            
            out.println(respondJSONObject);
        } finally {            
            out.close();
        }
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /**
     * Handles the HTTP
     * <code>GET</code> method.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /**
     * Handles the HTTP
     * <code>POST</code> method.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /**
     * Returns a short description of the servlet.
     *
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>
}
